Greenawalt's U.S. Pat. No. 3,521,310 discloses a composite pillow having laminated elements of different firmness, at least one relatively firm element for receiving the back of the neck of a supine person and a relatively softer adjacent element for receiving that person's occipital region. The patent also contains reference to the prior U.S. Pat. Nos. to Jones 655,087 and Forsland 2,880,428 as examples of variations of pillows for improving the comfort of the user, especially when the user is suffering from, say, a posture abnormality.
Although the Greenawalt pillow has achieved wide acceptance in its field, there is room for further improvement, and such improvement is the basis of the present invention. Fundamentally, this invention adds at least another dimension to the Greenawalt pillow by providing variability of a portion of one of the elements of greater firmness, thus yielding a pillow in which, for example, a central portion of the firmer element may be made less firm or more firm, depending upon the condition of the user, whereby the user, when turning from side to side will encounter portions flanking the central portion that are of different firmness than the central portion. Experience has shown that great benefits flow from a construction of this type, enabling the pillow to accommodate itself to conditions in which the person's condition requires one type of support for the supine position and a different type when the person's head is turned as when the person lies on one side.
The above result is achieved in one form of the invention by providing the one element with a central section, for example, including a compartment in which an inflatable bladder is disposed. This bladder is selectively inflatable to achieve a variety of firmness conditions relative to the flanking portions or sections which may remain of constant firmness, being formed, typically, of foamed urethane or its equivalent. The central element of a three-element pillow as in the Greenawalt patent identified above, may be of a relative soft density, or substantially less firm than the portions flanking the bladder. The bladder may be inflated to be harder or softer than its flanking portions. In another form of the invention, the central element may have a bladder also selectively inflatable, thus increasing the flexibility of the pillow. Further features and advantages will occur as preferred embodiments of the invention are disclosed herein.